Simultant material and method for manufacture thereof

ABSTRACT

A simulant material for simulating hazardous materials is provided. The simulant material includes a quantity of at least one explosive material and at least one inert material. The simulant material is a non-explosive material and is in the form of a homogenous, flexible and non-particulated material. Also provided is a method for manufacturing such a simulant material.

FIELD OF THE INVENTION

This invention relates generally to simulanting materials suitable foruse as training articles for training and calibration purposes, inparticular in the training of detecting dogs and security personnel, andfor calibrating sensitive analytical instruments. The materials are safefor handling (use, training, storage etc.) on the one hand and, on theother hand, are applicable in a variety of applications and compatiblewith different requirements.

BACKGROUND OF THE INVENTION AND STATUS OF PRIOR ART

Various methods and apparatus have been developed for detectingexplosives and other hazardous materials, e.g. chemical agents used inthe course of manufacturing nuclear weapons and chemical weapons, aswell as for detection of drugs. All such materials are hereinafter inthe specification and claims referred to collectively as hazardousmaterials.

As the concern of terrorist and criminal actions increases worldwide,the need to develop effective detection of hazardous materialsincreases, in particular when concerned with explosive materials,however not restricted thereto. One common way is use of detecting dogsand sensitive analytical technologies. To enable the training of suchdogs and their accompanying personnel, and/or the calibrating ofsensitive instruments, it has been necessary to use significantquantities of explosives (in most cases ‘neat’ materials) which pose ahazard as well as preventing dog training or instrument utilization insome critical or restricted areas. For example, during the training andutilization of detecting dogs, quantities of hazardous explosives arecarried in vehicles and placed in buildings which resulted in thepossibility of explosive detonation. The need for explosive materialsthus complicates detection training in populated areas such as airports,train stations, office buildings, etc. Furthermore, use of explosivematerials is admitted for authorized personnel, and also, speciallogistics are required, e.g. for storage, transportation, etc.

Similarly, calibrating of sensitive analytical instruments used for thedetection of explosives could only be accomplished by the presence of‘neat’ explosives, though in small quantities, but creating a hazard tothe handling personnel and to the equipment. Thus, there has been a needto develop safe methods of training explosives detecting dogs andpersonnel, and/or calibrating sensitive analytical instruments, andother applications, without the use of actual hazardous explosives.

Apart for safety issues and logistic complications concerned withhazardous materials, in the case of drugs detection training, adifferent issue evolves when utilizing actual drugs. This positions aproblem with criminals which may take advantage of different situationsand try some criminal acts.

U.S. Pat. Nos. 5,359,936 and 5,413,812 (the later divided out of U.S.Ser. No. 08/027,366, now said U.S. Pat. No. 5,359,936) disclose anexplosive simulant which is chemically equivalent to an explosive, butis not detonable. The simulants are manufactured either by slurrycoating technique to produce a material with a very high binder toexplosive ratio without masking the explosive vapor, or by coating inertbeads with thin layers of explosive molecules.

U.S. Pat. No. 5,648,636, (which is a Combination-In-Part of U.S. Ser.No. 08/221,568 and now said U.S. Pat. No. 5,413,812), discloses asimulant which is chemically equivalent to an explosive, but is notdetonable or explodable. The simulant is a combination of an explosivematerial with an inert material, either in a matrix or as a coating,where the explosive has a high surface ratio but small volume ratio. Thesimulant has particular use in the training of explosives detectingdogs, calibrating analytical instruments which are sensitive to eithervapor or elemental composition, or other applications where the hazardsassociated with explosives is undesirable but where chemical and/orelemental equivalence is required. The explosive simulants may befabricated by the use of standard slurry coatings to produce a materialwith a very high binder to explosive ratio without masking the explosivevapor, or by coating inert substrates with thin layers of explosivemolecules.

Other simulant materials are disclosed, for example, in U.S. Pat. Nos.5,756,006 and 5,958,299.

The present invention satisfies the need of providing simulant materialswhich are chemically equivalent to the actual hazardous materialsrequired for training and for operational uses, in nearly all aspects.However in the case of explosive materials simulants they cannotchemically react violently (no detonation, or deflagration, orexplosion), whereby the use of actual hazardous explosives iseliminated, thereby removing the hazards associated with the use ofexplosives. Furthermore, the simulant materials can also be used fordetection by instruments that do not rely on odors, e.g. density,crystallographic structure, chemical structure, etc.

In connection with explosives (defined herein to mean explosives as wellas gun and rocket propellants), an explosion is defined as a rapidenergy release while detonation is energy release at supersonicvelocities. Thus a non-detonable material may still be explodable.Therefore, safe materials are required, which are referred to in the artas Non-hazardous Explosives for Security, Training and Testing (NESTT).Hence safe use NESTT materials are those which are non-detonable andalso non-explodable.

The materials according to the above prior art patents are in the formof loose material, which have some deficiencies, such as causing anirritation to the sniffing dogs, difficulties in placing/applying thematerial, the need for special ‘sniffing containers’, etc.

Hereinafter in the specification and claims, the term ‘non-explosivematerial’ denotes a material which may be considered as anon-explodable, non-deflagradable and non-detonable material (i.e.compatible as a non class 1 material, as per definitions of the UNRegulations, the US Department Of Transportation (DOT) and other safetystandards).

It is an object of the present invention to provide simulant materialswhich as a primary condition are safe for handling, i.e. beingnon-explosive materials and substantially non-hazardous, and which onthe other hand are easy and cheap to manufacture and are easilyapplicable in a variety of forms and for different applications. It is afurther object of the present invention to offer a method formanufacturing simulant materials of the aforementioned type.

SUMMARY OF THE INVENTION

In view of the foregoing, the main object of this invention is toprovide a simulant material and articles made thereof, for simulatinghazardous materials useful as articles for training and calibrationpurposes, in particular in the training of detecting dogs and securitypersonnel, and for calibrating sensitive analytical instruments, whichis safe, requires simple logistics and eliminates crime activityoccurring in particular at the presence of drugs.

More particularly, an object of this invention is manufacture of anon-explosive simulant material comprising an explosive material and aninert material; wherein the simulant material is in the form of ahomogenous non-particulated material.

A salient feature of the invention is that the simulant materialsimulates explosive materials in four main aspects:

-   -   ‘odor print’ of the simulant material resembles that of the        simulated material;    -   the simulant material has like chemical structure properties of        the simulated material, though in substantially reduced ratio;    -   the simulant material has like crystallographic structure as of        the simulated material;    -   the simulant material is user and environmentally friendly and        safe.

The simulant material according to the present invention has manysignificant features and advantages, for example:

-   -   the simulant material is available in solid form or in paste        form, where it may be applied manually or by different        paste/putty applicators;    -   where the simulant material is in solid form it may be in the        form of spaghetti-like elements or as continuous sheet of        material, where it may be worked in different ways including        cutting, piercing and may be imparted any desired shape,        manually or by tools;    -   the simulant material may be readily used (self sustained)        eliminating use of special containers;    -   when in solid form, the simulant material is flexible/pliable;    -   the material may be adhered using readily available adhesives;    -   the material is foldable;    -   the simulant material is chemically and mechanically stable;    -   the simulant material is not effected by common organic        dissolvers, rendering it resistant in different operative        conditions;    -   the simulant material is free of non inherently associated        volatiles (e.g. solvents), whereby sniffing dogs or ‘sniffers’        (analytical instruments for detection of hazardous materials)        are not likely to be confused/misled;    -   a wide variety of ‘cocktails’ may be prepared for simulation of        different materials, however using one simulant article only.        Such cocktails may also involve simulation of explosive        materials, chemical agents and drugs, as well as deliberately        confusing/masking agents;    -   the simulant agent may comprise different additives, e.g. fire        retardants, pigment agents so as to offer visible        differentiation between such articles; metallic powder (ferrous,        tungsten, etc.) so as to render the simulant article detectable        also by magnetometers, etc;    -   the manufacturing process of the simulant material and articles        is rapid and at relatively low cost as compared with other        simulant materials.    -   the simulant material according to the invention is resistant to        hostile environments such as, humidity, sea water, corrosive        conditions, oils and fuels, extreme temperature condition (e.g.        in the range of about −54° C. to +70° C.), UV resistance,        radiation resistance.    -   density of the simulant material could be adjusted to resemble        that of the simulated material;    -   It is a further an object of the present invention to provide a        method for manufacturing simulant materials of the above        disclosed type, and simulant articles made thereof. Said method        comprising the steps of:        -   obtaining a mixture of at least one explosive material with            at least one inert material; and        -   mixing the materials to obtain a homogenous, flexible and            non-particulated, paste-like material.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the invention as well as other objects andfurther features thereof, reference is now made to the annexed drawingswherein:

FIG. 1 is a schematic representation of a manufacturing process of asimulant material according to a first embodiment of the presentinvention, where said simulant material is in paste form;

FIG. 2 is a schematic representation of a manufacturing process of asimulant material according to a first embodiment of the presentinvention where said simulant material is in solid form; and

FIGS. 3A-3E are samples of simulant material articles according to thepresent invention, formed in different shapes.

DETAILED DESCRIPTION OF THE INVENTION

Attention is first directed to FIG. 1 of the drawings illustrating aprocess for manufacturing simulant materials in accordance with thepresent invention. The manufacturing process utilizes a conventionalchemical engineering system comprising a plurality of hoppers 10, 12 and14 for containing a plurality of powdered or granulated material, and aplurality of liquid containers 16, 18, 20, 22 and 24 for containingdifferent liquids, as will be exemplified hereinafter.

Each of the hoppers and containers is fitted with a controllable port P,typically governed by a controlled processing unit (not shown) fordischarging precise amounts of material through said ports. Furthermore,each of the hoppers 10, 12 and 14 is fitted with a shaker/vibrator or ascrew-type feeder S to ensure proper flow of the solid particles (powderor granular).

Extending from each of the hoppers and containers there are ducts Dextending towards a large blender 24 which in the present example is asigma blade type blender operated by a motor M.

As disclosed hereinbefore, in accordance with one embodiment of theinvention, the simulant material is in a paste/putty like form which maybe obtained directly from the mixer 24. Such paste-like material maythen be removed from the mixer 24 and may either be collected intosuitable containers or putty dispensing tubes, e.g. of the type usedwith putty dispensers 30 as in FIG. 3A, wherein upon squeezing a trigger32 the paste/putty material 36 is dispensed and may be applied directlyon any surface whereby it is likely to adhere owing to its pasty nature.Alternatively, the paste-like simulant material 36 may be injected intocontainers of different shapes to simulate different conditions.

In accordance with a second embodiment, the simulant material is formedinto solid state and further attention is now directed also to FIG. 2 ofthe drawings illustrating further steps of the method for obtaining suchsolid simulant material. The paste/putty like stimulant materialobtained after the mixing stage in mixer 24 is then withdrawn andtransferred, e.g. by belt conveyor 40, to a vacuum extruder generallydesignated at 44. This stage of the process takes place under vacuumwherein the pasty material is extruded, whilst removing residual air andcompressing the pasty material into any desired form. In the particularembodiment, the material is formed into a continuous flat strip ofmaterial 50 placed on a second conveyor belt 54 which transfers thematerial into a drier 58 wherein the simulant material is solidified andreaches its final stage as a solid, though pliable/foldable materialcollected in the form of a roll of material 62, or flexible sheetsobtainable at various thicknesses.

The following is an example of a method of obtaining a simulantexplosive material. Hopper 10 comprises explosive material, e.g. RDX,hopper 12 comprises a powdered agent, e.g. silica, container 16comprises a siliconic polymer, (e.g. PDMS—polydimethyl siloxsane),container 18 comprises a cross-linking agent, (e.g. tetra-ethylsilicate) and container 20 comprises an organo-metallic catalyst (e.g.tin dibutyl laurate). The above ingredients are obtained and introducedinto the mixer 24. In accordance with one particular embodiment thefollowing volumetric ratio is used:

RDX  17%; Silica  30%; PDMS 49.4%;  Tetra-ethyl silicate 3.5%; Tindibutyl laurate 0.1%.

The ingredients are mixed for approximately 1 hour to thereby obtain ahomogenous paste-like material which is then transferred into the vacuumextruder 44 to compress the material under vacuum conditions, so as toremove residual air and obtain a pasty homogenous material, which isthen polymerized and cross-linked within the oven 58, e.g. by placing itovernight in a temperature of about 50° C.

However, if it is required to retain the simulant material in itspaste-like form, then the cross-linking agent (tetra-ethyl silicate inthe present example) and the catalyst (tin dibutyl laurate in thepresent example) are not fed into the mixture.

Having given the above example, it should be apparent to a person versedin the art that different parameters may be manipulated so as to obtainthe simulant material at different levels of viscosity. Such parametersmay be concentration of the additives or mixing speed and time at mixer24.

Amongst the additives which may be added into the mixture are, forexample, color agents, odor agents, different drugs so as to impart thesimulant material features also as a drug simulating material. Theexplosive material used for the mixture may be a single material or maybe a cocktail of materials to thereby simulate several such materials.As an example, RDX may be used side by side with PETN.

Other additives which may be used are, for, example, fire retardingagents, metallic powder detectable by metal detectors (magnetometers),e.g. ferrum powder or tungsten powder, the latter being preferable as ithas increased specific weight.

The hardened material obtained after the cross linking process at oven58 may be processed in different forms. For example, it may be kept as acontinuous sheet-like material (FIG. 3B). The material 64 may be cut byany suitable tool (scissors, knife, etc.) per demand. FIG. 3Cillustrates a simulant material 66 cut in the shape of a sole simulatinga sole-like article of the type commonly used by drug smugglers. In thiscase it is likely that the article is mixed also with drug simulatingagents. In the embodiment of FIG. 3B the simulant material 68 is cut inthe shape of a weapon, a pistol in the present example, and in this caseit is likely that a metallic powder is embedded in the simulantmaterial, to be detectable also by a magnetometer. FIG. 3A illustrates asimulant material 72 formed in the shape of a long rod, e.g. having asquare cross-section, a cylindrical cross-section, a tubularcross-section, etc. to be used in different applications.

Whilst some embodiments have been described and illustrated withreference to some drawings, the artisan will appreciate that manyvariations are possible which do not depart from the general scope ofthe invention, mutatis, mutandis.

1. A simulant material for simulating hazardous materials substantiallydevoid of non-inherently associated volatiles, comprising a quantity ofat least one explosive material and at least one inert material; whereinthe simulant material is a non-explosive material and is in the form ofa homogenous, flexible and non-particulated material.
 2. A simulantmaterial according to claim 1 in a solid or a pasty/putty form.
 3. Asimulant material according to claim 1, wherein the explosive materialis a cocktail of explosive materials.
 4. A simulant material accordingto claim 1 further comprising pigmentation agents which impart thesimulant material a distinguishable color.
 5. A simulant materialaccording to claim 1, further comprising at least one additive forsimulating one or more chemical war agent or for simulating one or moredrugs.
 6. A simulant material according to claim 1, further comprisingmasking agents that mask the scent of the at least one explosivematerial.
 7. A simulant material according to claim 1, being chemicallyor mechanically stable.
 8. A simulant material according to claim 1,further comprising metallic material in powdered form, homogeneouslydispersed within the simulant material, for imparting it with a magneticproperties.
 9. A simulant material according to claim 8, wherein themetallic material is tungsten.
 10. A simulant material according toclaim 1, being resistant to UV or IR radiation.
 11. A simulant materialaccording to claim 1, being heat resistant within the range of about−54° C. to +70° C.
 12. A simulant material according to claim 1, beingstable under X-ray radiation conditions.
 13. The simulant materialaccording to claim 1, wherein the simulant material is configured to besuitable for training of detection dogs, calibrating sensitiveanalytical instruments or for training personnel in working withdetection dogs or operation of sensitive analytical instruments. 14.Simulating articles made of a simulant material according to claim 1.15. A simulant material according to claim 1, in the form of a flexiblesheet.